I've just discovered I have a leaking vent pipe in my attic, with water located in 3 places A, B and C. If you click on this image it will take you to an enlarged view.

http://i226.photobucket.com/albums/dd285/dac122/House/PlumbingVentLeaks_sm.jpg (http://i226.photobucket.com/albums/dd285/dac122/House/PlumbingVentLeaks.jpg)

I'm pretty sure spot C is water dripping from spot A as it is directly below spot A. Spot B is on the top of that "T". Does it make sense for water to work, or wick up a joint like that? There is no water on the 45 elbow above it. Spot A is two 45 elbows glued together.

I've done PVC in the past and don't really want to tear out this entire run, particularly since I don't know how remove the end from the T at spot B and also how to remove it from the roofline.

For now I have some plastic down now to protect things until I can fix this, plus a vent cap outside (where vent penetrates roofing skirt) to prevent rain water from filling the pipe.

So what do you think?

Your attachment failed to come through. Water can't build up in a pipe unless there's backfall. While the vent is open to the outside it shouldn''t collect enough waterfor a leak to be obvious. Please post your drawing again using this thread. Tom

I've just discovered I have a leaking vent pipe in my attic, with water located in 3 places A, B and C. If you click on this image it will take you to an enlarged view.

http://i226.photobucket.com/albums/dd285/dac122/House/PlumbingVentLeaks_sm.jpg (http://i226.photobucket.com/albums/dd285/dac122/House/PlumbingVentLeaks.jpg)

I'm pretty sure spot C is water dripping from spot A as it is directly below spot A. Spot B is on the top of that "T". Does it make sense for water to work, or wick up a joint like that? There is no water on the 45 elbow above it. Spot A is two 45 elbows glued together.

I've done PVC in the past and don't really want to tear out this entire run, particularly since I don't know how remove the end from the T at spot B and also how to remove it from the roofline.

For now I have some plastic down now to protect things until I can fix this, plus a vent cap outside (where vent penetrates roofing skirt) to prevent rain water from filling the pipe.

So what do you think?
Thanks for the quick response. Here is the link to the full size image http://i226.photobucket.com/albums/dd285/dac122/House/PlumbingVentLeaks.jpg

You have built a trap into your vent line that's collecting water and must be removed and corrected. If it fills with water your entire vent system could be blocked. Shorten the pipe coming out of the first 45 and lower the next 45 as much as you can. This will give you some room to get by trapping the line by running the horizontal line over to a 90 and then exiting out the roof.
When you do all this your leak will be a thing of the past. Good luck, Tom

You have built a trap into your vent line that's collecting water and must be removed and corrected. If it fills with water your entire vent system could be blocked. Shorten the pipe coming outta the first 45 and lower the next 45 as much as you can. This will give you some room to get by trapping the line by running the horizontal line over to a 90 and then exiting out the roof.
When you do all this your leak will be a thing of the past. Good luck, Tom

Thanks Tom. I suspected I need to remove that section that is essentially a trap. And that's fine and that will be done.

However, I am concerned with water on the top lip of that T (spot B). How can I get water there? I checked all above that spot and cannot find a single drop. It just doesn't make sense.

I don't care how's dry the spot is this just had to dripped down from the leak above. There's no other explanation Regards, Tom

I don't care hows dry the spot is this just had to dripped down from the leak above. There's no other explanation Regards, Tom

Thanks.